Over at German.SE we have a question involving "the darkest of nights". I would like to know what this expression actually means, but I didn't find it in an online dictionary (e.g. leo.org, dict.cc, Cambridge Dictionary).
So what does this expression mean? Is it a figure of speech? I can imagine at least two meanings: It's the time of a particular night when it is darkest, or it's the darkest of a (not specified) number of nights.
German.SE was discussing superlatives (in the sense of grammar).
In that context, "the darkest of nights" simply means "a night darker than any other (of an unspecified number)."
You can use it in a literal sense, as in "it was the darkest of nights when the power grid failed and the moon was new."
Or, you can use it a figurative sense to convey that it was a night of great sorrow or some other sense of the word dark.
The darkest of nights could be a metaphorical expression to mean the very worst of bad times. Of course it could be interpreted literally to mean the darkest night among many nights.
I have seen this expression in literary texts. It means a very dark night, with no moonlight at all and it is used to enhance a feeling of foreboding. It can be called a hyperbole.
It might be better to use both halves in answeering your question. The first half, "Dark Night" refers to period of personal upheaval or crisis. Both halves: Dark Night, Early Dawn (DNED) is a phrase whose usage probably best elucidates the fuller context behind what a Dark Night exactly is. Transpersonal Studies usage can be summed up in the following;
"Dark Night...", as in Dark Night, Early Dawn typically can be used to refer to a period of great spiritual testing and, when coupled with "...Early Dawn", transformation. For more you might gloss over the book Summary of central metaphor in Dark Night, Early Dawn
Frequently a Dark Night is a period in which the mettle of a given subject is tested to such an extent as to not only unwind the topical or superficial egoic structures of the person, but when harnessed the crisis energy can additionally be utilized to unwind and deconstruct the foundational and subterranean structures.
Also, the actual crisis or context may not objectively warrant such a description, but the diligence and energy channelled into the situation and egoic structures involved would be sufficient to be a Dark Night experience to the subject.
When used in the superlative, there is an understanding of the Darkest Night laying bare the subject's entire self as a collection of dis-integrated parts. There is, in the sense of the Early Dawn, an opportunity to collect these fragmented elements of the person and to integrate them into a more cohesive personhood.
Literally, the phrase means a night that is darker than most nights, for example because it is a new moon, or clouds obscure the moon and stars. On such a night it may be difficult to see any danger until it is too late -- danger ranging from something on the ground that you trip over to wild animals or violent people attacking you. Thus such a night is considered scary. Thus figuratively the phrase can refer to a frightening time, like "When the dictator took over our country was plunged into the darkest of nights."
The context or setting under which it is used is more likely to reveal its particular intention, which is to say that both your's and Irene's perceptions are all correct.
I could, however, argue that its nuances and the ensuing ambiguities are what makes it more beautiful than a precise substitute. It is for you to decide whether its poetic undertone and its literal insensibility are contextually more significant than any fixed meaning someone else may offer.
